Antioxidants

May 13, 2002

The scientifically respected free-radical theory of aging36 serves as a basis for the prominent role that antioxidants have in the antiaging movement. The claim that ingesting supplements containing antioxidants can influence aging is often used to sell antiaging formulations. The logic used by their proponents reflects a misunderstanding of how cells detect and repair the damage caused by free radicals and the important role that free radicals play in normal physiological processes (such as the immune response and cell communication).37,38,39 Nevertheless, there is little doubt that ingesting fruits and vegetables (which contain antioxidants) can reduce the risk of having various age-associated diseases, such as cancer,40 heart disease,41,42 macular degeneration and cataracts.43,44 At present there is relatively little evidence from human studies that supplements containing antioxidants lead to a reduction in either the risk of these conditions or the rate of aging, but there are a number of ongoing randomized trials that address the possible role of supplements in a range of age-related conditions,45,46,47,48,49 the results of which will be reported in the coming years. In the meantime, possible adverse effects of single-dose supplements, such as beta-carotene,50 caution against their indiscriminate use. As such, antioxidant supplements may have some health benefits for some people, but so far there is no scientific evidence to justify the claim that they have any effect on human aging.51,52